Various instrumentation and control systems are designed with component redundancy so that the system may continue functioning in the unlikely event a component fails or is inoperative. For example, a system may include redundant sensors, which sense the same parameter and supply redundant sensor signals, and redundant electrical or electronic drivers, which drive redundant system components. The system may also include a controller, such as a real-time embedded electronic controller, that, among other things, receives, conditions, validates, and arbitrates the redundant sensor signals. The conditioned, validated, and arbitrated signals may then be passed along to control logic, which may be part of the controller itself, to compute appropriate control outputs that may be supplied to the redundant drivers. The controller may also validate and arbitrate redundant output signals, and supply a validated and arbitrated output signal to enable an appropriate one of the redundant drivers to implement the computed control output. The controller may also be used to implement fault reporting.
The design requirements and functional implementation for the above-described redundant signal validation, arbitration, and fault reporting can be quite complex. Moreover, the complexity may depend on a number of different parameters including, but not limited to, the number of redundant inputs, whether synthesized inputs are used, use of back-up signals, the number of built-in-test (BIT) signals that are used, and the number and variety of system states that may affect input signal and BIT signal validity. Some of these parameters may be system specific. Thus, the design and implementation of the validation, arbitration, and fault reporting may vary from application to application, and from system designer to system designer. This complexity may also result in significant software development efforts, which can increase system design and implementation costs.
Hence, there is a need for a common design framework for input and output signal validation, arbitration, and fault reporting for controllers, such as real-time embedded electronic controllers, that reduces system development complexity, and/or reduces system development cycle time and/or reduces development costs. The present invention addresses one or more of these needs.